"I believe that any questions as to my innocence must be examined by an objective investigation and a capable prosecution," Knox said in a statement at the time. "The prosecution responsible for the many discrepancies in their work must be made to answer for them, for Raffaele's sake, my sake, and most especially for the sake of Meredith's family."

Knox, an American citizen now living in Seattle, has said previously that she wouldn't return to Italy. Raffaele is expected to return to Florence for some of the retrial hearings, according to the BBC.

"We have absolute respect for the institutions and my son does not intend to run away," Sollecito's father, Francesco, told ANSA last week. "We are working without stop to show he is innocent in court."

Rudy Guede, who was born in the Ivory Coast but raised in Perugia, was convicted of Kercher's murder in 2008. Prosecutors believe he murdered Kercher in a sex game with Sollecito and Knox.

"The hopes are to have a complete, total, neutral and balanced trial which can then lead to a sentence which, whatever it is, is properly developed and well-reasoned," said Francesco Maresca, the Kercher family lawyer, in a statement Friday.

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